Locking push button mechanism



Feb. 10, 1959 R w sc s N 2,873,334

LOCKING PUSH BUTTON MECHANISM Filed Nov. 14, 1957 FIG. 4

FIG. 6

INVENTOP 85.5. W/RSCHl/VG ATTORNEY Telephone Laboratories, Incorporated, New York, N. Y., a corporatlonof New York Application November 14, 1957, Serial No. 696,546

, 7 Claims. (cl. 200-469) This invention relates to push button mechanisms and mo e' particularly to push button mechanisms of the lock ing 'type. r

In many kinds of electrical and mechanical equipment, push button mechanisms are employed as control or keying means. It is desirable in such equipment that the mechanisms be rugged, relatively insensitive to shock and reliable in operation. To accomplish this object, push button mechanisms of the locking type are commonly employed and these usually comprise one mechanism to lock the equipment in one condition and another mechanism to return the equipment to a normal condition.

In portable electrical testing equipment, for example, a telephone linemans handset, such arrangements are not especially suitable since they are bulky, cumbersome to operate, and often materially affect the weight of the equipment.

It is an object of this invention to provide a push button mechanism which is compact, rugged, reliable in operation, and relatively insensitive to shock and vibration.

It is another object of the invention to provide a push button mechanism of the locking type which is of simple construction and is conveniently adaptable to a considerable range of operating pressures and movements.

It is a specific object of the invention to provide a switching operating device for portable test equipment,

which does not materially affect the size and weight of such equipment, and is easy to operate.

A feature of the push button assembly of this invention is a peripherally secured, convex-concave spring washer or perforated diaphragm surrounding a portion of a push button and having a latching member or bracket secured to its convex face, said latching member being biased.

against a side of the push button by virtue of its attitude on the diaphragm, whereby upon partial depression of the button from its normal or unoperated position, the latching member encounters a shoulder on the button to latch it in the partially depressed or operated position.

A further feature of the invention lies in means associated with the push button for deflecting the diaphragm to a concave-convex condition upon full depression of the button to release the button from the latch by chang ing the position of said latch.

Another feature of the invention is a biasing means i for returning the push button, the diaphragm and the latching member to their normal positions and retaining them therein upon release of the button from its fully depressed position.

In an illustrative embodiment of this invention, a perforated diaphragm or washer is peripherally mounted in a housing with an inner portion of the push button within the diaphragm opening. The outer end of the button projects through an aperture in the housing. An inter? mediate enlargement of the button having inner and outer shoulders is pressed against the inner wall of the housing by biasing means. A U-shaped latching member having its legs secured to a face of the diaphragm em:

or unoperated condition of the mechanism, the diaphragm is flexed with its convex face toward the latching member,

which biases a transverse portion of the U-shaped bracket against the button at the enlargement. Thus, as previously indicated, a partial depression of the button allows the latching member to snap behind the outer shoulder of the enlargement to perform its latching function. Upon full depression of the button the inner shoulder of the enlargement flexes the diaphragm to an alternative position withits latch supporting face now concave. The latching member is thus deflected to a position outof contact with the button allowing return of the parts to their normal positions by the biasing means when the button is released.

These and other features of the invention will be more fully understood from the following detailed specifications taken in conjunction with the accompanying drawing;

in which:

Fig. 1 is a perspective view of an embodiment employing the principles of the invention with a portion broken away to show the parts thereof;

Fig. 2 is a cross section of the embodiment of Fig. 1 in the plane 2-2;

Fig. 3 is a longitudinal section of a switch employing the principles of the invention with the parts thereof in their normal positions;

Pg. 4 shows the switch of Fig. 3 in the locked condition;

, Fig. 5 indicates the switch in the releasing condition; and

Fig. discloses the switch parts an instant before returning to their normal positions.

As shown in Fig. 1 an interfitting cover 10 and base 11 comprise the housing 12 of the push button mechanism. The cover includes an aperture 13, an orificed flange portion 14, and is counterbored to a predetermined depth. The base includes a cup-like portion 15, an orificed flange portion 16, a central opening 17 and a boss 18 surrounding the opening. The cup-like portion 15 fits within the counterbore of the cover. The height of the cup-like por tion is slightly less than the depth of the counterbore thus defining an annular groove 19 in the otherwise cylindrical interior of the housing. The orificed flange portions 14 and 16 are aligned and held together by suitable fastening devices, for example, those shown in Fig. 3.

A spring-loaded plunger 20 is mounted within the housing and serves as the biasing means for the mechanism. The plunger includes a recess 21 in the head thereof. The shankof the plunger passes through the central opening 17. A helical spring 22 fits about the boss 18 and presses against the plunger head to bias the plunger toward diaphragm.

action of the spring-loaded plunger 20 against the button Patented Feb. 10, 1959 push button mechanism.

3 27. The portion 28 is normally surrounded by the bracket 24, the structural arrangement of these members being more clearly illustrated in Fig. 2. In the condition shown-inFigs. 1, and 3 the portion 28 of the button defleets, thebracket to the leftflexing. the legsZSand 26 for reasons which will become apparent hereinafter.

The operation ofthe push-button mechanism will be described with reference to Figs. 3, 4, 5- and 6 wherein the mcchanismis shown as a switching device. It should be understood that the mechanism has application to both mechanical and electrical equipment, but an electrical application has been selected arbitrarily for reasons for convenience in explanation. In Fig. 3- the push button mechanism is shown attached to a frame 29 and a set of contact members 30 and 31, is appropriately mounted (by'means not shown) in juxtaposition to the It is readily apparent that the switch button 27 and plunger in the normal or o position are relatively-insensitive to shock because of pressure due to the spring 22-, which is selectedto apply suflicient force to counteract'expected vibration in these members.

The switch contacts are closed asshown in Fig. 4'by depressing the button 27 which causes the plunger 20 to deflect the member to engage member 31. The bot ton while closing the contacts slides the portion 28 past the bracket 24' so that the inner shoulder of the portion 28 engages the diaphragm 23. The flexure in the bracket legs is released and they return to their regular position thereby resulting in the transverse portion of the bracket snapping in behind the shoulder. Release of the button with the bracket in this position locks the switch in the closed or on position since the upward thrust of the. spring-loaded plunger 20 against the button member is resisted by the stiifness of the diaphragm. The switch button travel for reaching the locked position is readily determined by an operator since an audible click is produced when the bracket snaps in behind the shoulder. It' is apparent that in the closed or on position the switch. button and] plunger are also insensitive toshock since downward movement of these members is resisted by increased pressure of the spring 22 and upward movement of these members is resisted by the stiffness of the diaphragm member.

To unlock the mechanism the switch button is fully depressed causing the'inner shoulder of the portion 28 to deflect the diaphragm to an outwardly concave configuration, as shown in Fig. 5. In so doing. the transverse portion of the bracket 24 is moved away from, the button simultaneously swinging clear of the portion 28; Care lease of the button, the enlarged shouldered portion has sufiicient clearance to pass within the bracket as the spring 22 returns the button and the plunger to their normal positions. The plunger in returning to its normal position allows the contact members (not shown) to open and subsequently presses against the diaphragm, as shown in Fig. 6, with sufiicient' force to return the diaphragm to its normal outwardly convexposition. The contact members 30 and 31 have not been shown in Figs. 5 and 6 for reasons of convenience. The enlarged shouldered portion is so spaced from the plunger that it returns to its normal position abutting the housing 12 before the diaphragm is returnedto its normal position by the plunger. The bracket member, as a consequence, is biased against the shoulder and is ready to snap behind the shoulder when the button is depressed on the next operation.

movements". Thus, these characteristics of them'echanism make it desirable for a wide variety of mechanical and electric'al'applieation. The disclosed mechanism is 'es'pe til) - 4 cially suitable for portable test equipment, since his small in size, easy to operate and provides operation which is relatively insensitive to shock and vibration.

It is to be understood that the above-described embodiments are merely illustrative of the principles. of the invention and applicant does not intend to limit the invention to the particular embodiments shown herein. Numerous other embodiments may be devised. by those skilled in the art without departing from the spirit an scope of the invention.

What is claimed is:

1. A push button mechanism comprising a housing having an. aperture in one wall, a push button.- having an outer end projecting through the aperture, an inner end connected to and urged outwardly'by biasing means, and an enlarged shouldered section intermediate the ends thereof; a diaphragm mounted within the housing and encircling saidbutton adjacent the inner end. thereofgt a latching member embracing the enlarged section and secured to the diaphragm, said latching member. being. biased. against the enlarged section by virtue of its at titude ou the diaphragm, whereby a; partial movement of thebutton against the biasing. means allows the latch: ingmernber torest on a shoulder of the enlarged section of the button to latch the button, and wherebyfurther' movement of the butt-on in the same direction deflects the diaphragm to urge the latching member away from the button to unlatch the button.

2.A push button mechanism comprisingv a housing havingan aperture in one wall, a push button ha'vingan outer end projecting through the aperture, a'n-iuner. end connected to and urged outwardly by biasing means,- and 'an enlargedv shouldered section intermediate the, ends thereof; a convex-concave diaphragm'mounted" within the housing. and encircling saidbutton adjacent the inner end thereof, a latching member attached to the. convex face of said. diaphragm and embracing the enlarged section, said latching member being biased against. the enlarged section by virtue of its attitude on the diaphragm, whereby a partial movement of the button against the biasing means allows the latching member to rest on a shoulder of the enlarged section of the button to latch the. button, and whereby further movement of the button in the same direction deflects the diaphragm. to urge the. latching member away from the button to unlatch the button.

3. A push button mechanism comprising a housing having an aperture in one wall, a push buttonhaving an outer end projecting throughthe aperture,-.anl inner end conueictedto and urged outwardly by. biasing means an enlarged shouldered section of the button abutting the inner wall of the housing; a convex-concave diaphragm. peripherally mounted within the housing. and encircling,

said button adjacent the inner end thereof, a latch mem:

ber attached to the convex face of said diaphragm and:

attitude on thc diaphragm,.whereby a partialmovemcnt.

of the. buttonagainst the biasing means vallows the. latch memberto rest on a shoulder of the enlarged section of the button to latch the button, and whereby further movement of the button in the same direction deflects the diaphragm to'urge the latch member away from the button to disengage said member. s p o v 4; A push button mechanism comprising a housing having an aperture in one wall, a push button having an outer end projecting through the aperture, an inner end conn'ectedt'o and urged outwardly by biasing means, and.

an, enlarged shouldered section intermediate the, ends thereof and within the housing; a convex-concave diatachedt'othe convex face ohsaid"diaphraginpsaidbracket.

embracing the enlarged section of said 'button with its transverse portion biased against the enlarged section by virtue of its attitude on the diaphragm, whereby a partial movement of the button against the biasing means allows the transverse portion to rest on a shoulder of the enlarged section of the button to latch, the button, and whereby further movement of the button in the same direction deflects the diaphragm to urge the U-shaped bracket away from the button to unlatch the button.

5. A push button mechanism comprising a housing having an aperture in one wall, a push button having an outer end projecting through the aperture, an inner end connected to and urged outwardly by a spring-loaded plunger, said plunger being in axial alignment with said button and positioned in a wall of the housing opposite the wall including the aperture; an enlarged shouldered section intermediate the ends of said button and within the housing, a diaphragm mounted within the housing and encircling said button adjacent the inner end thereof, a U-shaped bracket having leg portions twisted to face the transverse portion of said bracket, said leg portions secured to the diaphragm, said bracket embracing the enlarged section with the transverse portion biased against the enlarged section by virtue of its attitude on the diaphragm, whereby a partial movement of the but ton against the biasing means allows the transverse portion to rest on a shoulder of the enlarged section of the button to latch the button, and whereby further movement of the button in the same direction deflects the diaphragm to urge the U-shaped bracket away from the button to unlatch the button. 7

6. A push button mechanism comprising a housing having an aperture in one wall, a perforated diaphragm peripherally mounted in the housing, a push button having an inner end within the diaphragm opening, an outer end of the button projecting through the aperture, an intermediate enlargement of the button being pressed against the inner wall of the housing by biasing means, a

U-shaped bracket having leg portions secured to a face of a diaphragm, said bracket embracing the enlargement of the button and being biased against the enlargement by virtue of its attitude on the diaphragm, whereby a partial depression of the button allows the bracket to snap behind the enlargement of the button to latch the button and whereby further movement of the button in the same direction deflects the diaphragm to urge the U-shaped bracket away from the button to unlatch the button.

7. A push button mechanism comprising a housing having an aperture in one wall, a perforated diaphragm peripherally mounted within the housing, a push button having an inner end Within the diaphragm opening, an outer end of the button projecting through the aperture, an intermediate enlargement of the button having inner and outer shoulders, said outer shoulder being pressed against the inner wall of the housing by biasing means, a U-shaped latch having leg portions secured to a face of the diaphragm, said bracket embracing the enlargement of the button and being biased against the enlargement by virtue of the attitude of the leg portions on the diaphragm, whereby a partial depression of the button allows the latch to snap behind the outer shoulder of the enlargement to latch the button and whereby further movement of the button in the same direction causes the inner shoulder to deflect the diaphragm to urge the U- shaped latch away from the button thereby disengaging said latch.

References Cited in the file of this patent UNITED STATES PATENTS 1,591,149 Waltamath July 6, 1926 FOREIGN PATENTS 912,769 France July 25, 1945 

